Actor and comedian Tracy Morgan has been critically injured after a tractor-trailer rammed into his chauffeured limousine bus, setting off a chain-reaction crash that left one member of his entourage dead and two others seriously hurt.

A truck driver from Georgia was charged with death by auto in connection to the crash, prosecutors said.

Middlesex County prosecutors said 35-year-old Kevin Roper also faces four counts of assault by auto. His bail was set at $US50,000 ($A54,100), and he was expected to turn himself in later on Saturday.

Morgan, the former Saturday Night Live and 30 Rock cast member, was returning from a stand-up comedy show in Delaware when his Mercedes limo bus carrying seven people overturned on the New Jersey Turnpike near Cranbury Township at about 1am on Saturday, state police Sergeant 1st Class Greg Williams said.

James McNair, 62, of Peekskill, New York, a passenger in the limo bus, died at the scene, Williams said. Morgan, 45, and Jeffrey Millea, 36, of Shelton, Connecticut, were flown from the accident scene to Robert Wood Johnson Hospital, where they were in critical condition, hospital spokesman Peter Haigney said.

A fourth passenger, comedian Ardie Fuqua Junior, was also in critical condition, while a fifth passenger, comic Harris Stanton, was treated and released, Haigney said.

Two others in the limo were unhurt, including the driver.

Morgan remains in the intensive care unit at the hospital.

“His family is now with him and he is receiving excellent care,” spokesman Lewis Kay said in a statement.

“We don’t anticipate much of a change in his condition today but will provide a further update once more information becomes available.”

Williams said the tractor-trailer driver apparently failed to notice slow traffic ahead and swerved at the last minute in a vain attempt to avoid a crash.

But it smashed into the back of the limo, prompting a chain-reaction crash with a second tractor-trailer, an SUV and two cars.

Morgan performed comedy standup on Friday night at Dover Downs Hotel & Casino. His appearance at the Fillmore Charlotte in North Carolina on Saturday night was cancelled.

Morgan, a New York City native, joined SNL in 1996 and was on the sketch-comedy program for seven years before leaving to star in The Tracy Morgan Show in 2003. That show lasted just one season.

In 2006, Morgan found a long-running role on NBC’s hit show 30 Rock and received an Emmy nomination for best supporting actor for 30 Rock in 2009.

Morgan grew up fatherless, one of five siblings in Brooklyn, where he helped raise and support the family.

He once called his gift for being funny “a defence mechanism” for his miserable circumstances. As a teen, he started doing comedy on the streets to supplement the family’s welfare income.

In recent years, he has struggled with alcoholism and drunken driving arrests. He had a successful kidney transplant in late 2010.

Morgan has three grown sons by a previous marriage and a daughter, Maven Sonae, born last July to his fiancee, Megan Wollover.

His films include Jay and Silent Bob Strike Back, The Longest Yard, First Sunday, Rio and Why Stop Now.